Part of #2524

Rationale: In order to make it easier to integrate PMD into other tools, it might be better to use the de-facto-standard slf4j.
We could then provide some basic simplelogger configuration in our binary distribution, but integrations have full freedom on which logging framework they want to use.

This would at slf4j-api as an additional compile-time dependency and maybe slf4j-impl as runtime dependency in our pmd-bin-xxx.zip distribution.

Currently we are using java util logging.

Tasks:

• Decide on the logging backend (log4j, logback, ...) and provide a default runtime + test
  configuration
  • Simplelogger from slf4j: That's a simple logger implementation without additional transitive dependencies that can still be configured (selection of loggers) - https://www.slf4j.org/api/org/slf4j/simple/SimpleLogger.html
  • Logback: It would have support for color output on the console - https://logback.qos.ch/
  • We start with simplelogger to keep it simple. The implementation can be switched later, if needed.
• Integrate it into the CLI flags (-debug)
• Fix dist (add missing dependency, provide default simplelogger.properties)
• Test dist
• Fix ant (AntLogger)
• Remove logback-classic from apex-jorje
• Create a custom PMD rule to avoid usage of java.util.logging - only slf4j should be allowed. In build-tools.
• Refactor logging statements (split into tasks/PRs for each pmd module)